The invention relates in general to refrigeration systems and more specifically to means for providing heat to an evaporator coil which is used in a refrigeration system.
A common problem associated with refrigeration systems, such as transport refrigeration units, relates to the evaporator unit and defrosting the evaporator coil in a timely and efficient manner. The prior art has addressed the problem in several ways.
One approach has been to provide for a flow of hot gas over the frosted coil. This method has not proven to be efficient and causes problems with the refrigerant which tends to migrate back to the condenser.
Another method provides for the use of simple electrical resistance, spaced at a fixed distance from the evaporator coils. To provide radiant heat this method, however, fails to provide for defrosting in a timely or even manner.
It can therefore be seen from the above that there is a need in the field for an efficient way in which to effectively defrost an evaporator coil and avoid creating other problems in the refrigeration system.
Accordingly it is an object of the present invention to provide for means which overcome the problems associated with the frosting or icing of evaporator coils for refrigeration systems.
It is another object to provide an efficient and economical means for heating an evaporator coil yet retain the ease of serviceability and replacement of the hearing means.
It is yet another object of the present invention to provide an effective means for providing heat on demand to an evaporator coil.
It is a further object of the present invention to provide heating means which are integral to an evaporator coil which shorten defrost time.
It is another object of the present invention to provide for electrical heating means which defrost a refrigeration evaporator coil in an efficient and timely manner.